| Mechanism of inactivation of gamma-aminobutyric acid-alpha-ketoglutaric acid aminotransferase by 4-amino-5-halopentanoic acids. | |
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MedLine Citation:
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PMID: 7225323 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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(S)-4-Amino-5-halopentanoic acids were previously shown to irreversibly inhibit pig brain gamma-aminobutyric acid--alpha-ketoglutaric acid aminotransferase, and a mechanism for the inactivation was proposed (Silverman, R. B., & Levy M. A. (1980) Biochem. Biophys. Res. Commun. 95, 250). Evidence is presented to show that these compounds are mechanism-based inactivators, and experiments are described to elucidate their mechanism of action. The enzyme must be in the pyridoxal phosphate form for inactivation to occur, the gamma proton of the inactivators is removed in a rate-determining step, and one fluoride ion is released from 4-amino-5-fluoropentanoic acid per active site labeled. The change in the optical spectrum of the enzyme during inactivation suggests that the coenzyme is converted into the pyridoxamine phosphate form. Every turnover of inactivator leads to an inactivation event, i.e., the partition ratio is zero. |
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Authors:
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R B Silverman; M A Levy |
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Publication Detail:
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Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: Biochemistry Volume: 20 ISSN: 0006-2960 ISO Abbreviation: Biochemistry Publication Date: 1981 Mar |
Date Detail:
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Created Date: 1981-07-20 Completed Date: 1981-07-20 Revised Date: 2007-11-14 |
Medline Journal Info:
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Nlm Unique ID: 0370623 Medline TA: Biochemistry Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 1197-203 Citation Subset: IM |
Export Citation:
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| MeSH Terms | |
Descriptor/Qualifier:
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4-Aminobutyrate Transaminase
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antagonists & inhibitors* Amino Acids / pharmacology* Animals Brain / enzymology Deuterium Isotope Labeling Kinetics Spectrophotometry Structure-Activity Relationship Swine Transaminases / antagonists & inhibitors* |
| Grant Support | |
ID/Acronym/Agency:
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NS 15703/NS/NINDS NIH HHS |
| Chemical | |
Reg. No./Substance:
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0/Amino Acids; 7782-39-0/Deuterium; EC 2.6.1.-/Transaminases; EC 2.6.1.19/4-Aminobutyrate Transaminase |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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